基于视图的过滤绝对是要走的路。你可以使用类似于我在下面编码的示例。筛选树时的另一种常见做法是在筛选树时切换到列表视图，因为列表不需要显示需要显示其后代的隐藏节点。
这绝对是可怕的代码（我刚才试图削减所有可能的角落），但它应该足以让你开始。只需在搜索框中键入查询并按 Enter，它就会筛选 JTree 的默认模型。（仅供参考，前90行只是生成的样板和布局代码。
package com.example.tree;
import java.awt.BorderLayout;
public class FilteredJTreeExample extends JFrame {
private JPanel contentPane;
private JTextField textField;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
FilteredJTreeExample frame = new FilteredJTreeExample();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the frame.
*/
public FilteredJTreeExample() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 450, 300);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
contentPane.setLayout(new BorderLayout(0, 0));
setContentPane(contentPane);
JPanel panel = new JPanel();
contentPane.add(panel, BorderLayout.NORTH);
GridBagLayout gbl_panel = new GridBagLayout();
gbl_panel.columnWidths = new int[]{34, 116, 0};
gbl_panel.rowHeights = new int[]{22, 0};
gbl_panel.columnWeights = new double[]{0.0, 1.0, Double.MIN_VALUE};
gbl_panel.rowWeights = new double[]{0.0, Double.MIN_VALUE};
panel.setLayout(gbl_panel);
JLabel lblFilter = new JLabel("Filter:");
GridBagConstraints gbc_lblFilter = new GridBagConstraints();
gbc_lblFilter.anchor = GridBagConstraints.WEST;
gbc_lblFilter.insets = new Insets(0, 0, 0, 5);
gbc_lblFilter.gridx = 0;
gbc_lblFilter.gridy = 0;
panel.add(lblFilter, gbc_lblFilter);
JScrollPane scrollPane = new JScrollPane();
contentPane.add(scrollPane, BorderLayout.CENTER);
final JTree tree = new JTree();
scrollPane.setViewportView(tree);
textField = new JTextField();
GridBagConstraints gbc_textField = new GridBagConstraints();
gbc_textField.fill = GridBagConstraints.HORIZONTAL;
gbc_textField.anchor = GridBagConstraints.NORTH;
gbc_textField.gridx = 1;
gbc_textField.gridy = 0;
panel.add(textField, gbc_textField);
textField.setColumns(10);
textField.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent evt) {
TreeModel model = tree.getModel();
tree.setModel(null);
tree.setModel(model);
}
});
tree.setCellRenderer(new DefaultTreeCellRenderer() {
private JLabel lblNull = new JLabel();
@Override
public Component getTreeCellRendererComponent(JTree tree, Object value,
boolean arg2, boolean arg3, boolean arg4, int arg5, boolean arg6) {
Component c = super.getTreeCellRendererComponent(tree, value, arg2, arg3, arg4, arg5, arg6);
DefaultMutableTreeNode node = (DefaultMutableTreeNode) value;
if (matchesFilter(node)) {
c.setForeground(Color.BLACK);
return c;
}
else if (containsMatchingChild(node)) {
c.setForeground(Color.GRAY);
return c;
}
else {
return lblNull;
}
}
private boolean matchesFilter(DefaultMutableTreeNode node) {
return node.toString().contains(textField.getText());
}
private boolean containsMatchingChild(DefaultMutableTreeNode node) {
Enumeration<DefaultMutableTreeNode> e = node.breadthFirstEnumeration();
while (e.hasMoreElements()) {
if (matchesFilter(e.nextElement())) {
return true;
}
}
return false;
}
});
}
}
当您真正实现它时，您可能希望创建自己的TreeNode和TreeCellRenderer实现，使用不那么愚蠢的方法来触发更新，并遵循MVC分离。请注意，“隐藏”节点仍会呈现，但它们非常小，以至于您无法看到它们。但是，如果您使用箭头键在树中导航，您会注意到它们仍然存在。如果你只需要一些有效的东西，这可能就足够了。
编辑
以下是 Mac OS 中树的未筛选和已过滤版本的屏幕截图，显示空格在 Mac OS 中可见：
